Magnetron



Patented Dec. 21,1948 1 1 UNITED STATES PATENT OFFICE MAGNETRON Ernest(J. Okress, Montclair, N. 1., assignor to Westinghouse ElectricCorporation, East Pittsburgh, Pa., a corporation of PennsylvaniaApplication January 28, 1943, Serial No. 473,829

6 Claims. (Cl. 315-40) This invention relates in general to magne-Figure 5 is a section similar to Fig. 3 showing a trons and particularlyto anode strapping modified construction of strap and mounting therein.therefor.

It has been heretofore determined as desirable In the specificembodiment of the invention to electrically couple or strap alternateparti- 1 illustrated in said drawing, the reference charactions inmagnetrons in order to operate in the ter Ill designates the anode bodyportion of the N magnetron shown as of metal and of a generallycylindrical configuration. This body portion is provided at its exteriorwith opposite longitudip s mode more t v y t having been n nal endflanges. projecting above and below the.

dOne by a plurality of lengths of Wire each Stredtop and bottom generalend planes of the main dlins an intervening partition w the ends part ofthe anode body. End plates or closures o ere to t e partitions beingeeupled- The l2 fit upon and are sealed with respect to the p oc s pp ythe Coupling Wires is tedious-1 respective flanges thereby establishingenclosed It s o desirable that y Strapping means be 15 end spaces l3across the top and bottom of the of a character readily reproduced inquantity, d d

o permanent shape and vme e a The anode body is hollowed longitudinallysec y p e These deslderatums are with a middle or coaxial cavity M fromwhich tirely lacking in the P r art method of pradiate resonant cavitiesI5 separated by parti- P niegnetlons. that their accomplishment ac tionsit of equal length and symmetric in shape Constitutes e p y bject of thepr se t and disposition. The ends of these several par-.

inventiontitions are in a common plane and it is those p y, an object Ofthe v t on s t ends which constitute the ends of the anode body Providea One-Piece Strap at One end of the and those planes which constitutethe endplanes netron which is duplicated by a like Strep at the 25 ofthe anode body. While the particular radiatother end thereof. ingcavities l5 are shown herein as each having Anot er O ject o theinvention is o aveid a slot formation next the middle cavity M whichpossibility o inadvertent Contact of the strap outwardly expands into acylindrical formation, with an interve pa tit o o te ing the inventionis not confined to that structure, partitions. 3i). inasmuch as othercavity shapes, such as de- Another object of the invention is to keepthe icted inprior application (of which an a m st pp g means from puding above the end is my application Ser. No. 460,376, filed October;pl e o the several partitions or a de body. 1,1942, and assigned t thesame assignee as the. generally, to e-VOid fi nt capacity effectspresent one) may be used and the present invenin different magnetrons bythe strapping means. tion'applied thereto.

St l furt r O j of the invention Will l End spaces iii are utilized,inter alia, forintrop s the description Proceeds b by direct ductionradially thereof, appropriate lead-in ecita i thereof and y implicationo the wires H for a filament l8 here shown utilized co teXtfor heating acylindrical cathode l9 coaxiallydis- Referring to t e acco p y drawingsn -10 posed within the middle cavity Id. The cathode which like numeralsof reference indicate simihas a length substantially the axial length ofthe: lar parts throughout the several views: anode body and opposite theends of the cathode Figure 1 is a sectional plan of a magnetron arediscs20 spaced beyond the end planes of the taken immediately below a coverplate thereof as anode and carried by insulators 2| in the ends on lineII of Fig. 2; of the cathode. Each said disc forms a con- Figure 2 is avertical cross section of the magnection between the respective lead-inwire and netron on a diametric line II-II of Fig. 1; filament-endsituated in the particular end space Figure 3 is a section on largerscale than Fig. 2, in which the disc is located. The lead-in wires takenon the same line II-II of Fig. 1 but with are appropriately sealed withrespect to the inthe greater part of the anode broken away and terior ofthe device and said device is evacuated showing the association of thestraps with the so the; electron flow will function in vacuum.- anodeand their relation to each other; An output coupling or loop 22representative of,

Figure 4 is a perspective view of the two straps any desired energytransfer means has a sealed with projected relation of the straps toeach other connection through the outer wall of the body shown in dottedlines; and ortion into one of the radiating cavities 15,-saidloop beingshown in the arbitrarily selected disclosure as in a cavity 90 displacedfrom the filament lead-in connections, but other selection of cavity inwhich to position the said loop may be made provided the probed portionis satisfactory for this arrangement. For convenience of description,the. cavity. in which the,, ,1oop located will be referredijto .as theoutputycavity.

Around the middle cavity l lan'd"at each" end of the anode body there isprovided an annular...

stepped recess providing what may be identified as a p step 3 (see Fig.3) and a shallow stem-1':

24, the deeper step being for clearance purposes dered Withouthindranceby any parts of the deand the shallower step being formountingiajs'trapp 25 therein. The shallow step 24 has. great'eridi;ameter than the deeper step and between steps is a cylindrical partconstituting a 'riser zfii The" vice .i'n-iront of. such place ofsoldering. Only a verysmallportionof the effective anode surface isremoved in making the stepped recess for acccmmoda'ting the: strap, theshallow step preferstrap 25 mentioned has portions thereof. resting onthe shallow step 2 3 ofalternate partitions and other. portions bridgingover, or otherwise avoidingfi contact" with intervening partitions by;pyer: lying" andbeing spaced fromthe' deeper step'23f Explained more indetailsaicl strap 25in' the present showing is a flat ring, the,innerdiamet'er of'iwliich is' preferably. equal to the diameter-of f themiddle or" cathode cavity: The outer part ofthe: ring presentssuccessive sections offdifie r ent" diameters such that each narrowsection 21 i's'endwi'se betweenttwo wide sections 2 8*-'and"ea.0h widesection 28' is? endwise --between two narrow sections zli The diameter,of the circle defined by; theouter" arcuat'ei edges" of the narrow"secitibnsis'lessithan' the diameter of said riser 26 so. there will'be"spacingof the narrow sections fi'omsaid-ri'ser and'fromthedeeper'step'ZSi." The wider sections 2.8 may be considered'ast'abs orcars projecting froma: narrow ring" at spaced intervals'and in theplane-of th-e ring. The length" oft'liewider section or tab '28 is equalto the-widthof the. contiguous part, of the anode partitions; whereasnarrow section 2 'l' exceeds thel'ength of? the wider section b'y awalueequal to-twicethe gap of ai radiating cavity i where it'mak-es-entryunder-the ringlntot'ne" middle cavity. Thisconstruction results inaminimum amount of the ring, overlying or being oppositethe' ends of theradiating cavities l5. The outer'marg-irialpart of" the" under faceof 1each wider section 'rest's uporrthecontiguousface-of shallow step 24',pref-- erablycompletely filling saidstep Without overlap at the-ends;and is soldered orotl'iervv-is'e secured; implace and given goodelectrical contact witht-lie partition to which applied.

Asempha-sized'by the'dotted line projection of; wider sections of eachstrap-upon-the'other, in- Figure 4; it will beclear 'that' the alternatepartitions joined-bythe strap at one end of the anode are entirely outof contactfromthe strap at the' other" end of the anode and that". thepartitions Bridged overor skipped by the strap at-oneend of tlieanodeare connected by thestrap:at the" other-endi If desired; thestrapsmay be con-- structed' with. a perpendicular lip'at thexoutenpe-zlriptieral "extremity ofthe' wider sections; as shown in=Figure 5 In thatview; the-straps 25' are'sim ilar in-most'respeot's to the onesalcove-described; liavingnarrow sections 21f" and wider sections: 28*with the-outerrim 29pf the wider section bentperpendicular tothe planeof thestrap so it'may be introduced into" a corresponding: groove 3m inthe anodebody HS After the strapis placed; an edge of 'the" anode-n'extthe'sa'id" groovemay birpeened; as at 3 I to hol'd 'theistrap assembledfSol'c'l'erihgihi addition to orin pla'ce of the peenev ably being justthe thickness of the strap material so the upper face of.the strapis inthe same plane as the upper face of the anode body. Furt'liermore;capacity loading-between t'l'i'e-strapand thepartitions bridged overwithout connection" thereto can be accurately controlled in manufa 'cture; and is not lef t' to jud'gment of the operator assembling-thedevice: These and other --advari-'- tagesa uses and structures will beunderstoodby those skilled in the art and as falling within the scope ofthe invention, which, through necessity, as specifically shownin thedrawing, isto be con..- s'id'ered from its generic aspects under theterms employed and} description- 'given' 'herein.

I 1-. A strapped anode-fora magnetron" compris-- ing an anode -b'od'y*providing plurality of radiating partitions"the-longitudinal endswhereof are inoo'mmon planes and form the end plane of the anode;sai'd'anode having ai-circul'ar recess in the end thereof; said re'cessli'eing -steppedso as tobe deeper next one periphery oftlierecesstlfanithe other, and astrap overlying the deeper-fparti ofi saidreeess outlof centactfit'h'ereat from the anode, said strap havingprojections in the loser deem part of the: recess andsin: contact:-with; and: sup portedtby selected? ones;of'csaidrpartitionse 2; Astrappedi anode for: aimagnetron' comprise ing an anode body providingaipluraiity' ofi radi ating tpartitionsstheslongitudinalendsiwhere'ofare inzcommon planes: and format'he' endiplan'eofTit-heanode; saidranodeinaviing a circulars-recessIinithe' end thereofand next the radially inwardemargin of'fsaid :partiti'ons; said-:recessbeing-i ,steppedtso/ as t'ozbe deeper;nextpnerp'eriphery'ofthe recessthan: th'eother; andta strapi overly-ingsthe deeper part of said recess;out of contactsv thereat from the: anode; saidstrap havingprojectionsinvt'he-lessi deep partidfi the" recess extending to the periphcryof"the reciess and: in contact with and: sup-- pontedby selectedlones ofsaid partitions;

3. A strapped anode for a magnetron comprise ing anLa-nod'e body:providing aipluralityl offra'diatingpartitions the-longitudinalendsi'whereof are in common:planesiandiform .theendiplane of. the.anode, said anodehavingrar circular recessin:;.the end thereof-andnexttthe: radiallyainward margin:- of said partitions, saidrecess1being;stepped with a; deeper. part1; next the smallerperiphery-of; the recesSLand'Zwless.deepkpantinextzthelarger.periphecry" of the recess; and a stinap overlyingvthe deeper. partof'isaidjreccsseout of'contact thereati from the: anode; saith-strap.having. radially: cute-E ward: prcj ections imthe less. deeprpart; ofthe-- re? cess extendlngctoithe peniphery ofiithe recessiand:imcontactwith andfisupported:byrseleotednneszof said-partitions; v

4. A strapped anode :fon eta-magnetron comprise ing an anode bodyproviding a plurality of radiating partitions the longitudinal endswhereof are in common planes and form the end planes of the anode, saidanode having a circular recess in the end thereof, said recess beingstepped so as to be deeper next one periphery of the recess than theother, and a substantially flat strap having thickness approximating thedepth of the outermost part of said recess and an outer diameter lessthan the inner diameter of said outermost part and having radiallyoutward projections projecting into and applied flatwise upon saidoutermost part, whereby said strap is in the said end plane of the anodeoverlying the deeper part of the said recess and making sole contactwith the anode by support of said projections on the outermost part ofselected ones of said partitions.

5. A magnetron comprising an anode having a longitudinal cylindricalcavity for the cathode, a cathode in said cavity, a ring-like straphaving an inside diameter substantially equal to the diameter of thecylindrical cathode cavity, said anode providing partitions radiatingfrom said cathode cavity, and said strap having half as many projectionsthereon as there are partitions, i

said projections making contact with an equal number of partitions andconstituting the only contacting portions of the said strap with theanode.

6. A magnetron comprising an anode having a longitudinal cylindricalcavity for the cathode, a cathode in said cavity, a ring-like straphaving an inside diameter substantially equal to the diameter of thecylindrical cathode cavity, said anode providing partitions radiatingfrom said cathode cavity, and said strap having half as many projectionsthereon as there are partitions, said projections making contact with anequal number of partitions and constituting the only contacting portionsof the said strap with the anode, and each said projection having alength in a direction circumferentially of the ring equal to thethickness of the part of the partition where said projection contactssaid partition.

ERNEST C. OKRESS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,063,342 Samuel Dec. 8, 19362,069,867 Wilson Feb. 9, 1937 2,128,237 Dallenbach Aug. 30, 19382,147,159 Gutton et a1 Feb. 14, 1939 2,154,758 Dallenbach Apr. 18, 19392,163,157 Samuel 1 June 20, 1939 2,167,201 Dallenbach July 25, 19392,201,216 Baier et al May 21, 1940 2,417,789 Spencer Mar. 18, 1947FOREIGN PATENTS Number Country Date 215,600 Switzerland Oct. 16, 1941445,084 Great Britain Apr. 2, 1936

